When you create a OpenReadCompletedEventHandler delegate, you identify the method that will handle the event. To associate the event with your event handler, add an instance of the delegate to the event. The event handler is called whenever the event occurs, unless you remove the delegate.
publicstaticvoid OpenResourceForReading2 (string address)
WebClient client = new WebClient ();
Uri uri = new Uri(address);
client.OpenReadCompleted += new OpenReadCompletedEventHandler(OpenReadCallback2);
The following method is called when the download completes.